Synthetic aperture radar imagery of range traveling ocean waves

The imaging processes of range traveling waves are investigated by taking account of both the cross section and range bunching. The SAR transfer function and image modulation functions are defined to describe the relative importance and the coupling effects of the two contributions. It is shown that in low to moderate sea states, where the major variation in backscatter arises from local surface tilt, the image modulation by the cross section is enhanced by range bunching and the effect increases with increasing wave slope and also with decreasing look angle. For ocean waves in high sea states with a small variation in the cross section and steep wave slopes, range bunching may become an important mechanism for the interpretation of the images formed by SAR with small look angles